In one prior art approach, a separate system is installed on the customer's internal network to do testing of email messages. This approach is limited in that it only tests internal email flow and does not test email sent to and from Internet locations. Boxtone®, IPsentry®, and Microsoft® MOM are examples of products that test emails internal to a system. Using this type of testing system requires that the software package be brought into the customer network and be installed in a real, live production environment. Moreover, this approach does not scale economically across multiple customer installations.
Another known email testing methodology uses an external system to test that the inbound mail port, for example port 25, is accessible. This approach does not test that email has actually arrived inbound, nor that email can be sent outbound. Systrack® is an example of a product that implements this type of approach. Products such as Systrack® only test to verify that some software agent is responding on port 25 and do not verify that email is successfully received from an Internet source.
Another approach tests that email at an inbound mail port has arrived inbound via Pop3 access. This approach also does not test that an email can be sent outbound. Nimsoft® and Alertsite® are product examples that implement this method. This type of testing requires that the Pop3 protocol must be enabled on the Microsoft® Exchange server and opened on firewalls for Internet access, thus exposing the internal system to outside threats. This is not desired in a typical corporate environment.